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1.
Vet Res Commun ; 48(1): 507-517, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38051451

RESUMO

The increasing frequency of methicillin-resistant (MR) staphylococci in humans and animals need special attention for their difficult treatment and zoonotic character, therefore novel antimicrobial compounds on a natural base against antibiotic-resistant bacteria are requested. Currently, bacteriocins/enterocins present a new promising way to overcome this problem, both in prevention and treatment. Therefore, the preventive and medicinal effect of dipeptide enterocin EntA/P was evaluated against MR Staphylococcus epidermidis SEP3/Tr2a strain in a rabbit model, testing their influence on growth performance, glutathione-peroxidase (GPx) enzyme activity, phagocytic activity (PA), secretory (s)IgA, and jejunal morphometry (JM). Eighty-eight rabbits (aged 35 days, meat line M91, both sexes) were divided into experimental groups S (SEP3/Tr2a strain; 1.0 × 105 CFU/mL; dose 500µL/animal/day for 7 days, between days 14 and 21 to simulate the pathogen attack), E (EntA/P; 50 µL/animal/day, 25,600 AU/mL in two intervals, for preventive effect between days 0 and 14; for medicinal effect between days 28 and 42), E + S (EntA/P + SEP3/Tr2a; preventive effect; SEP3/Tr2a + EntA/P; medicinal effect) and control group (C; without additives). Higher body weight was recorded in all experimental groups (p < 0.001) compared to control data. The negative influence/attack of the SEP3Tra2 strain on the intestinal immunity and environment was reflected as decreased GPx activity, worse JM parameters and higher sIgA concentration in infected rabbits. These results suggest the promising preventive use of EntA/P to improve the immunity and growth of rabbits, as well as its therapeutic potential and protective role against staphylococcal infections in rabbit breeding.


Assuntos
Bacteriocinas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Masculino , Feminino , Coelhos , Animais , Staphylococcus epidermidis , Resistência a Meticilina , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteriocinas/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Glutationa/farmacologia , Glutationa/uso terapêutico , Peroxidases/farmacologia , Peroxidases/uso terapêutico , Imunoglobulina A/farmacologia , Imunoglobulina A/uso terapêutico
2.
Biomater Sci ; 11(23): 7616-7622, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37828832

RESUMO

Nanoprobes for efficient tumor-targeted imaging and therapy are urgently needed for clinical tumor theranostics. Herein, inspired by the heterogeneity of the tumor microenvironment, we report a covalent organic framework (COF)-derived biomimetic nanozyme for precise tumor-targeted imaging and NIR-II photothermal-catalysis-enhanced chemotherapy (PTCEC). Using a crystalline nanoscale COF as the precursor, a peroxidase-like porous N-doped carbonous nanozyme (PNC) was obtained, which was cloaked with an M1 macrophage cell membrane (M1m) to create a multifunctional biomimetic nanoprobe for tumor-targeted imaging and therapy. The M1m coating enabled the nanoprobe to target cancer cells and tumor tissues for highly efficient tumor imaging and drug delivery. The peroxidase-like activity of the PNC allowed for the conversion of intratumoral H2O2 into toxic ˙OH that synergized with its NIR-II photothermal effect to strengthen the chemotherapy. Therefore, highly efficient tumor-targeted imaging and NIR-II PTCEC were realized with an M1 macrophage mimic nanoprobe. This work provides a feasible tactic for a biomimetic theranostic nanoprobe and will inspire the development of new bioactive nanomaterials for clinical tumor theranostic applications.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Humanos , Peróxido de Hidrogênio , Nanomedicina Teranóstica/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Peroxidases/uso terapêutico , Linhagem Celular Tumoral , Nanopartículas/química , Microambiente Tumoral
3.
Acta Biomater ; 158: 625-636, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36608895

RESUMO

The antioxidant system of tumor cells severely impairs reactive oxygen species (ROS)-mediated tumor therapy. Despite extensive attempts to attenuate the antioxidant capacity by eliminating ROS scavengers such as glutathione (GSH), nicotinamide adenine dinucleotide phosphate (NADPH) over-expressed in the tumor microenvironment can regenerate GSH from glutathione disulfide (GSSG), hence weakening ROS-induced oxidative damage. Therefore, engineering a nanoplatform capable of depleting both NADPH and GSH is extremely significant for improving ROS-mediated tumor treatment. Herein, a synergetic antioxidant inhibition strategy is proposed to attenuate intracellular antioxidant capacity for hypoxic tumor therapy. In this context, both porous Prussian blue nanoparticles (PPB NPs) and cisplatin prodrug [cis-Pt (IV)] in the nanoplatform can oxidize GSH to directly reduce GSH levels, while PPB NPs also enable NADPH depletion by peroxidase-mimicking to impair GSH regeneration. Furthermore, PPB NPs with catalase-mimicking activity catalyze H2O2 decomposition to alleviate tumor hypoxia, thus reducing the generation of GSH and boosting singlet oxygen (1O2) production by Chlorin e6 (Ce6) for enhancing oxidative damage. Experimental results prove that the nanoplatform, denoted as PPB-Ce6-Pt, can induce remarkable tumor cells apoptosis and ferroptosis. Importantly, a simple loading method and the use of Food Drug Administration (FDA)-approved materials make PPB-Ce6-Pt have great potential for practical applications. STATEMENT OF SIGNIFICANCE: The antioxidant system in tumor cells disables ROS-mediated tumor therapy. Besides, extensive attempts aim at depleting GSH without considering their regeneration. Therefore, we developed a synergetic strategy to attenuate intracellular antioxidant capacity for hypoxic tumor therapy. PPB-Ce6-Pt nanoplatform could not only directly reduce GSH levels but also deplete NADPH by peroxidase-mimicking to impair GSH regeneration. In addition, PPB-Ce6-Pt nanoplatform could catalyze H2O2 decomposition to alleviate tumor hypoxia, thus reducing the generation of GSH and boosting 1O2 production by Chlorin e6 (Ce6) for increasing oxidative damage. Then, intracellular ROS boost and redox dyshomeostasis induced remarkable tumor cells apoptosis and ferroptosis. Importantly, a simple loading method and the use of biosafety materials made the nanoplatform have great potential for practical applications.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Antioxidantes/farmacologia , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio/química , NADP/farmacologia , NADP/uso terapêutico , Estresse Oxidativo , Neoplasias/tratamento farmacológico , Glutationa/metabolismo , Nanopartículas/química , Peroxidases/farmacologia , Peroxidases/uso terapêutico , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/química , Microambiente Tumoral
4.
Acta Biomater ; 153: 431-441, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36174937

RESUMO

Photodynamic therapy (PDT) has become a promising cancer treatment due to in situ generation of cytotoxic reactive oxygen (ROS); however, it remains limited by the hypoxia of tumor microenvironment (TME) and penetration depth of laser. Herein, we developed a kind of GSH-/H2O2-responsive copper-encapsulating magnetic nanoassemblies (MNSs) for switchable T1-weighted magnetic resonance imaging (MRI) and enzyme-like activity potentiating PDT of cancer. MNSs were rationally constructed using the chelation effect of copper ions (Cu2+) with polyacrylic acid-coated ultrasmall iron oxide nanoparticles (UIONPs). After uptake by tumor cells, the incorporated Cu2+ of MNSs was reduced to Cu+ through the intracellular GSH, which resulted in the disassembly of MNSs accompanied by the "silenced" MR signal shifting to a positive state. Sequentially, the generated Cu+ manifested peroxidase-like activity, catalyzing local H2O2 in TME to cytotoxic ·OH for chemodynamic therapy. Furthermore, Cu2+ and UIONPs could decompose H2O2 to O2, thus providing extra oxygen necessary for enhancing the PDT effect of photosensitizer IR-780. Finally, IR-780-loading MNSs (MNSs@IR-780) under laser irradiation significantly inhibited tumor growth and prolonged the survival of gastric MGC-803 tumor-bearing mice. Therefore, this study provides a versatile nanoplatform as a tumor-responsive theragnostic agent. STATEMENT OF SIGNIFICANCE: Tumor hypoxia and penetration depth of laser severely hindered the PDT of cancer. Valence-convertible metal ions (VCMI, e.g., Cu2+/Cu+, Fe3+/Fe2+) have been reported as Fenton-like agents disintegrating H2O2 to O2 to enhance PDT. Tumor-delivery of VCMI is of essential importance for in situ triggering of a Fenton-like reaction. We thereby developed magnetic nanoassemblies (MNSs) to encapsulate Cu2+ and load photosensitizer (IR-780). Stimulated by GSH and H2O2, MNSs performed catalase/peroxidase-like activity that provided extra O2 for PDT and catalyzed H2O2 to ·OH for CDT. Consequently, IR-780-loading MNSs under laser irradiation significantly inhibit the tumor growth due to effective tumor delivery of Cu2+ and IR-780. This study might offer a feasible nanoplatform for tumor-delivery of metal ions and drugs.


Assuntos
Antineoplásicos , Neoplasias , Fotoquimioterapia , Camundongos , Animais , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Cobre/farmacologia , Peróxido de Hidrogênio/farmacologia , Linhagem Celular Tumoral , Fotoquimioterapia/métodos , Microambiente Tumoral , Antineoplásicos/farmacologia , Neoplasias/patologia , Imageamento por Ressonância Magnética , Oxigênio/farmacologia , Peroxidases/farmacologia , Peroxidases/uso terapêutico
5.
Clin Transl Med ; 12(9): e1060, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36149789

RESUMO

BACKGROUND: Small-cell lung cancer (SCLC) molecular subtypes have been primarily characterized based on the expression pattern of the following key transcription regulators: ASCL1 (SCLC-A), NEUROD1 (SCLC-N), POU2F3 (SCLC-P) and YAP1 (SCLC-Y). Here, we investigated the proteomic landscape of these molecular subsets with the aim to identify novel subtype-specific proteins of diagnostic and therapeutic relevance. METHODS: Pellets and cell media of 26 human SCLC cell lines were subjected to label-free shotgun proteomics for large-scale protein identification and quantitation, followed by in-depth bioinformatic analyses. Proteomic data were correlated with the cell lines' phenotypic characteristics and with public transcriptomic data of SCLC cell lines and tissues. RESULTS: Our quantitative proteomic data highlighted that four molecular subtypes are clearly distinguishable at the protein level. The cell lines exhibited diverse neuroendocrine and epithelial-mesenchymal characteristics that varied by subtype. A total of 367 proteins were identified in the cell pellet and 34 in the culture media that showed significant up- or downregulation in one subtype, including known druggable proteins and potential blood-based markers. Pathway enrichment analysis and parallel investigation of transcriptomics from SCLC cell lines outlined unique signatures for each subtype, such as upregulated oxidative phosphorylation in SCLC-A, DNA replication in SCLC-N, neurotrophin signalling in SCLC-P and epithelial-mesenchymal transition in SCLC-Y. Importantly, we identified the YAP1-driven subtype as the most distinct SCLC subgroup. Using sparse partial least squares discriminant analysis, we identified proteins that clearly distinguish four SCLC subtypes based on their expression pattern, including potential diagnostic markers for SCLC-Y (e.g. GPX8, PKD2 and UFO). CONCLUSIONS: We report for the first time, the protein expression differences among SCLC subtypes. By shedding light on potential subtype-specific therapeutic vulnerabilities and diagnostic biomarkers, our results may contribute to a better understanding of SCLC biology and the development of novel therapies.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Biomarcadores , Linhagem Celular Tumoral , Meios de Cultura , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/uso terapêutico , Peroxidases/genética , Peroxidases/metabolismo , Peroxidases/uso terapêutico , Proteômica , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/metabolismo
6.
J Control Release ; 350: 332-349, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36028045

RESUMO

Chemodynamic therapy (CDT), an emerging tumor-specific therapeutic modality, is frequently restrained by insufficient intratumoral Fenton catalysts and increasingly inefficient catalysis caused by the continuous consumption of limited H2O2 within tumors. Herein, we engineered a pH-responsive bortezomib (BTZ) polymer prodrug catalytic nanoreactor (HeZn@HA-BTZ) capable of self-supplying Fenton catalyst and H2O2. It is aimed for tumor-specific chemo/chemodynamic therapy via oxidative stress and endoplasmic reticulum (ER) stress dual-amplification and macrophage repolarization. A catechol­boronate bond-based hyaluronic acid-BTZ prodrug HA-DA-BTZ was modified on Hemin and Zn2+ coordination nanoscale framework (HeZn), an innovative CDT inducer, to construct He-Zn@HA-BTZ. He-Zn@HA-BTZ with good stability and superior peroxidase-like activity preferentially accumulated at tumor sites and be actively internalized by tumor cells. Under the cleavage of catechol­boronate bond in acidic endo/lysosomes, pre-masked BTZ was rapidly released to induce ubiquitinated protein aggregation, robust ER stress and elevated H2O2 levels. The amplified H2O2 was further catalyzed by HeZn via Fenton-catalytic reactions to produce hypertoxic •OH, enabling cascaded oxidative stress amplification and long-lasting effective CDT, which in turn aggravated BTZ-induced ER stress. Eventually, a dual-amplification of oxidative stress and ER stress was achieved to initiate cell apoptosis/necrosis with reduced BTZ toxicity. Intriguingly, He-Zn@HA-BTZ could repolarize macrophages from M2 to antitumor M1 phenotype for potential tumor therapy. This "all in one" prodrug nanocatalytic reactor not only enriches the CDT inducer library, but provides inspirational strategy for simultaneous oxidative stress and ER stress based excellent cancer therapy.


Assuntos
Neoplasias , Pró-Fármacos , Bortezomib/farmacologia , Catálise , Catecóis , Hemina/uso terapêutico , Humanos , Ácido Hialurônico/química , Peróxido de Hidrogênio/metabolismo , Macrófagos/metabolismo , Nanotecnologia , Neoplasias/tratamento farmacológico , Peroxidases/uso terapêutico , Polímeros/uso terapêutico , Pró-Fármacos/uso terapêutico , Agregados Proteicos
7.
Acta Biomater ; 151: 600-612, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35953045

RESUMO

The depletion of reactive oxygen species (ROS) by glutathione (GSH) and oxidative stress induced protective autophagy severely impaired the therapeutic effect of chemodynamic therapy (CDT). Therefore, how to construct a CDT treatment nanosystem with high yield and full utilization of ROS in tumor site is the main issue of CDT. Herein, a multifunctional cascade bioreactor based on mesoporous Mo-doped Cu9S5 (m-MCS) nanozymes loaded with L-Arginine (LA), abbreviated as m-MCS@LA, is constructed for realizing enhanced CDT promoted by ultrasound (US) triggered gas therapy. The m-MCS based on the catalytic performance of multivalent metal ions, which were served as nanozymes, exhibit enhanced Fenton-like and glutathione (GSH) peroxidase-like activities in comparison to Cu9S5 nanoparticles without Mo-doping. Once placed in tumor microenvironment (TME), the existence of redox couples (Cu+/Cu2+ and Mo4+/Mo6+) in m-MCS enabled it to react with hydrogen peroxide (H2O2) to generate ·OH for achieving CDT effect via Fenton-like reaction. Meanwhile, m-MCS could consume overexpressed GSH in tumor microenvironment (TME) to alleviate antioxidant capability for enhancing CDT effect. Moreover, m-MCS with mesoporous structure could be employed as the carrier to load natural nitric oxide (NO) donor LA. US as the excitation source with high tissue penetration can trigger m-MCS@LA to produce NO. As the gas transmitter with physiological functions, NO could play dual roles to kill cancer cells through gas therapy directly, and enhance CDT effect by inhibiting protective autophagy simultaneously. As a result, this US-triggered and NO-mediated synergetic cancer chemodynamic/gas therapy based on m-MCS@LA NPs can effectively eliminate primary tumor and achieved tumor-specific treatment, which provide a possible strategy for developing more effective CDT in future practical applications. STATEMENT OF SIGNIFICANCE: The depletion of reactive oxygen species (ROS) by glutathione (GSH) and oxidative stress induced protective autophagy severely impaired the therapeutic effect of chemodynamic therapy (CDT). Herein, a multifunctional cascade bioreactor based on mesoporous Mo-doped Cu9S5 (m-MCS) nanozymes loaded with L-Arginine (m-MCS@LA) is constructed for realizing enhanced CDT promoted by ultrasound (US) triggered gas therapy. The m-MCS with double redox couples presents the enhanced enzyme-like activities to perform cascade reactions for reducing GSH and generating ROS. LA loaded by m-MCS can produce NO triggered by US to inhibit the mitochondria protective autophagy for reactivating mitochondria involved apoptosis pathway. The US-triggered and NO-mediated CDT based on m-MCS@LA can effectively eliminate primary tumor through the high yield and full utilization of ROS.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Antioxidantes/farmacologia , Arginina/farmacologia , Autofagia , Linhagem Celular Tumoral , Glutationa/farmacologia , Humanos , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Mitocôndrias/metabolismo , Neoplasias/tratamento farmacológico , Óxido Nítrico/farmacologia , Peroxidases/farmacologia , Peroxidases/uso terapêutico , Espécies Reativas de Oxigênio , Microambiente Tumoral
8.
Curr Alzheimer Res ; 19(6): 420-439, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692129

RESUMO

INTRODUCTION: Alzheimer's disease (AD) is a progressive, neurodegenerative disease that severely affects individuals' cognitive abilities, memory, and quality of life. It affects the elderly population, and there is no permanent prevention or cures available to date, treatments mainly aiming to alleviate the symptoms as and when they appear. Alternate therapeutic approaches are being researched constantly, and there is a growing focus on phytomedicine, herbal medicine, organic compounds, and ayurvedic compounds for the treatment of AD. METHODS: The current study aims to provide an extensive review of these plants against AD from the currently existing literature. Most relevant keywords like Alzheimer's Disease, phytomedicines, ethnic medicines, the role of phytomedicine in neuroprotection, common phytomedicines against AD, etc., were used to select the plants and their metabolites effective in treating AD. The study focuses on six plants: Panax ginseng, Ginkgo biloba, Bacopa monnieri, Withania somnifera, Curcuma longa, and Lavandula angustifolia. Their active components have been studied along with neuroprotective properties, and evidence of in-vitro, pre-clinical, and clinical studies conducted to prove their therapeutic potential against the disease have been presented. RESULTS: All plants envisaged in the study show potential for fighting against AD to varying degrees. Their compounds have shown therapeutic effects by reversing the neurological changes such as clearing Aß plaque and neurofibrillary tangle formation, and ameliorative effects against neurodegeneration through processes including improving concentration, memory, cognition and learning, higher working and cue memory, improved spatial memory, inhibition of NF-κB expression, inhibiting the release of pro-inflammatory cytokines, inhibition of AChE and lipid peroxidase enzymes, and reduction of interleukin levels and tumor necrosis factor-alpha. CONCLUSION: The present review is a comprehensive and up-to-date analysis supported by the evidentiary proofs from pre-clinical studies, meta-analyses, and review papers related to natural phytochemicals' impact on neurodegenerative disorders like AD.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Idoso , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , NF-kappa B , Fator de Necrose Tumoral alfa , Qualidade de Vida , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Peroxidases/uso terapêutico , Lipídeos
9.
Cell Signal ; 93: 110307, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35288240

RESUMO

Glutathione peroxidase 8 (GPx8) belongs to a family of enzymes that have a critical role in controlling levels of reactive oxygen species (ROS). GPX family members have been associated with several cancers. Here, we examined the role of GPx8 in esophageal squamous cell carcinoma (ESCC). Immunohistochemical staining and western blot analysis were used to study the clinical significance of GPx8 in ESCC tissue. GPx8 was further evaluated in cells by MTT assay and colony formation. RT-PCR, western blot, immunofluorescence staining, TUNEL assay, TEM, and flow cytometry were used to assess the molecular mechanism underlying endoplasmic reticulum (ER) stress associated with GPx8 in ESCC cells. Xenografted tumor growth was used to assess the in vivo role of GPx8. We found that GPx8 was overexpressed in both ESCC cell lines and tumor tissue. GPx8 knockdown significantly suppressed ESCC proliferation and induced autophagy and apoptosis in ESCC cell lines, whereas GPx8 overexpression led to increased proliferation and inhibition of apoptosis. GPx8-mediated inhibition of apoptosis was associated with the ER stress pathway through inositol-requiring enzyme 1 (IRE1) and Jun N-terminal kinase (JNK). Knockdown of GPx8 in xenograft models of ESCC resulted in a significant reduction in tumor weight and volume, which was further reduced with IRE1 or JNK inhibitors. Our study suggests that GPx8 regulates apoptosis and autophagy in ESCC through the IRE1/JNK pathway in response to ER stress. Targeting this pathway might be a potential therapeutic strategy for ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases , Peroxidases/metabolismo , Peroxidases/uso terapêutico , Proteínas Serina-Treonina Quinases
10.
Mol Med Rep ; 24(1)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33982776

RESUMO

Sialoperoxidase and myeloperoxidase are the two main peroxidase enzymes found in the oral cavity. Sialoperoxidase is present in salivary secretions and in the biofilms that line the oral surfaces, while myeloperoxidase is abundant in the dento­gingival sulcus area. In the presence of hydrogen peroxide (H2O2), oral peroxidases catalyze the oxidation of the pseudohalide anion thiocyanate (SCN­) to hypothiocyanite (OSCN­), a strong oxidant that serves an antimicrobial role. Furthermore, oral peroxidases consume bacteria­produced H2O2 and could help inactivate toxic carcinogenic and genotoxic substances. Numerous in vitro studies have reported the antibacterial, antimycotic and antiviral role of peroxidases, suggesting possible applications in oral therapy. However, the use of oral hygiene products incorporating peroxidase systems has not yet been shown to be beneficial for the treatment or prevention of oral infections. This paradox reflects our incomplete knowledge of the physiological role of peroxidases in a complex environment, such as the oral region. While hygiene is crucial for restoring oral microbiota to a symbiotic state, there are no data to suggest that the addition of a peroxidase per se can create a dysbiotic state. Recent investigations have associated the presence of peroxidase activity with gram­positive cocci microbial flora, and its insufficiency with dysbiosis has been linked to pathologies, such as caries, periodontitis or infections of the oral mucosa. Therefore, oxidants generated by oral peroxidases appear to be an essential ecological determinant for oral health through the selection of a symbiotic microbiota capable of resisting oxidative stress. The objective of the present review was to update the current knowledge of the physiological aspects and applications of oral peroxidases in clinical practice.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Boca/enzimologia , Boca/microbiologia , Higiene Bucal/métodos , Peroxidases/farmacologia , Peroxidases/uso terapêutico , Animais , Mimetismo Biológico , Humanos , Oxidantes/metabolismo
11.
Transplant Proc ; 39(5): 1332-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17580134

RESUMO

Increasing evidence has shown that reactive oxygen species (ROS) are important mediators in liver ischemia/reperfusion injury(IRI). ROS include hydrogen peroxide (H(2)O(2)), superoxide anion (O(-2)), and hydroxyl radical (HO(-)), which may be generated by activated Kupffer cells in the liver, contributing to reperfusion injury. Hepatic IRI is a multistep process that damages liver graft function. To establish a series of therapeutic strategies to improve the outcome of liver transplantation, a good understanding of the mechanisms of IRI is essential. However, the detail mechanisms of how ROS lead to hepatocyte damage in IRI remains unclear. The aim of this review was to describe recent developments in the field of oxidative stress research. The first part of this review focused on the key roles and possible mechanisms of ROS in hepatic IRI. The second part of this review summarizes some findings including novel and classic antioxidant methods to ameliorate the hepatocyte damage during IRI.


Assuntos
Antioxidantes/uso terapêutico , Precondicionamento Isquêmico/métodos , Circulação Hepática , Transplante de Fígado/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Ácido Ascórbico/uso terapêutico , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/metabolismo , Glutationa Peroxidase/uso terapêutico , Humanos , Falência Hepática/cirurgia , Transplante de Fígado/métodos , Peroxidases/uso terapêutico , Peroxirredoxinas , Espécies Reativas de Oxigênio/análise , Traumatismo por Reperfusão/prevenção & controle , Tiorredoxinas/uso terapêutico
12.
Trends Mol Med ; 11(12): 571-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16290020

RESUMO

H(2)O(2) is a reactive oxygen species that has drawn much interest because of its role as a second messenger in receptor-mediated signaling. Mammalian 2-Cys peroxiredoxins have been shown to eliminate efficiently the H(2)O(2) generated in response to receptor stimulation. 2-Cys peroxiredoxins are members of a novel peroxidase family that catalyze the H(2)O(2) reduction reaction in the presence of thioredoxin, thioredoxin reductase and NADPH. Several lines of evidence suggest that 2-Cys peroxiredoxins have dual roles as regulators of the H(2)O(2) signal and as defenders of oxidative stress. In particular, 2-Cys peroxiredoxin appears to provide selective, specific and localized control of receptor-mediated signal transduction. Thus, the therapeutic potential of 2-Cys peroxiredoxins is clear for diseases, such as cancer and cardiovascular diseases, that involve reactive oxygen species.


Assuntos
Modelos Biológicos , Estresse Oxidativo/fisiologia , Peroxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Sequência de Aminoácidos , Humanos , Dados de Sequência Molecular , Peroxidases/genética , Peroxidases/uso terapêutico , Peroxirredoxinas , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Alinhamento de Sequência
13.
Clin Cancer Res ; 6(12): 4915-20, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11156252

RESUMO

Human peroxiredoxin II (Prx II) has been known to function as an antioxidant enzyme in cells. Using head-and-neck cancer cell lines, we investigated whether Prx II expression is related to the resistance of cells to radiation therapy in vivo and in vitro, and whether a Prx II antisense serves as a radiosensitizer. Increased expression of Prx II was observed in tissues isolated from the patients who did not respond to radiation therapy, whereas Prx II expression was weak in tissues from the patients with regressed tumors. Enhanced expression of Prx II in UMSCC-11A (11A) cells was also observed after treatment with gamma radiation. This increased expression conferred radiation resistance to cancer cells because overexpression of Prx II protected 11A cells from radiation-induced cell death, suggesting that blocking Prx II expression could enhance radiation sensitivity. Treatment of 11A cells with a Prx II antisense decreased induction of Prx II, enhancing the radiation sensitivity. From these results, we suggest that stress-induced overexpression of Prx II increases radiation resistance via protection of cancer cells from radiation-induced oxidative cytolysis and that a Prx II antisense can be used as a radiosensitizer.


Assuntos
Antioxidantes/uso terapêutico , Oligonucleotídeos Antissenso/uso terapêutico , Peroxidases/uso terapêutico , Tolerância a Radiação/efeitos dos fármacos , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Northern Blotting , Morte Celular/efeitos dos fármacos , Terapia Combinada , Relação Dose-Resposta à Radiação , Raios gama , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Immunoblotting , Peroxidases/metabolismo , Peroxirredoxinas , Radiossensibilizantes/uso terapêutico , Fatores de Tempo , Células Tumorais Cultivadas
14.
J Prosthet Dent ; 76(3): 292-6, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8887803

RESUMO

Patients who have undergone irradiation for head and neck tumors commonly have xerostomia. Loss of the protective constituents normally found in saliva leaves patients at greater risk for development of significant dental pathologic disorders, including gingival and periodontal disease. Periodontal disease and tooth extractions are currently accepted as etiologic factors for the development of osteoradionecrosis. This double-blind crossover trial was conducted to assess the efficacy of a dentifrice containing salivary peroxidase elements in the reduction of gingivitis in a population of patients with irradiated cancer. Subjects were instructed to brush with the dentifrice provided. Plaque and gingival index values were obtained and statistically compared with baseline values. A weak positive effect was found between use of the dentifrice and a reduction in gingival inflammation. Patient compliance was a limiting factor in this treatment effect. The results suggest possible efficacy for the dentifrice in augmenting traditional measures of postradiation oral health maintenance.


Assuntos
Irradiação Craniana/efeitos adversos , Dentifrícios/uso terapêutico , Doenças da Gengiva/prevenção & controle , Peroxidases/uso terapêutico , Saliva/enzimologia , Proteínas e Peptídeos Salivares/uso terapêutico , Estudos Cross-Over , Placa Dentária/etiologia , Placa Dentária/prevenção & controle , Índice de Placa Dentária , Dentifrícios/química , Método Duplo-Cego , Feminino , Doenças da Gengiva/etiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Masculino , Cooperação do Paciente , Índice Periodontal , Resultado do Tratamento , Xerostomia/complicações , Xerostomia/etiologia
15.
Acta bioquím. clín. latinoam ; 23(4): 435-41, dic. 1989. tab
Artigo em Espanhol | LILACS | ID: lil-95787

RESUMO

Se detectaron anticuerpos antiespermáticos en tracto genital femenino inferior de mujeres estériles con maridos normospérmicos y test post coital anormal como única anomalía. Se estudió la distribución de glicoconjugados tipo N y de los receptores de los oligosacáridos pertenecientes a glicoconjugados de este tipo, en la superficie de los espermatozoides recuperados de eyaculado, del tracto vaginal y de moco cervical. Se correlacionaron los resultados de ambos estudios, encontrándose redestribución de glicoconjugados y receptores en espermatozoides obtenidos del tracto genital femenino. Esta redestribución no estaría relacionada a la presencia de anticuerpos.


Assuntos
Humanos , Masculino , Feminino , Anticorpos/imunologia , Espermatozoides/imunologia , Glicoproteínas , Infertilidade/diagnóstico , Muco/imunologia , Peroxidases/uso terapêutico , Testes Imunológicos
16.
s.l; s.n; 1988. 196 p. ilus, tab.
Tese em Espanhol | LILACS | ID: lil-121787

RESUMO

Este trabajo fue realizado en una población de 7.200 pacientes de la consulta diaria de la Unidad de Ginecología, Reproducción y Salud Integral, de Valencia, las cuales asistieron en un período de dos años, entre julio de 1982 a julio de 1985. Se seleccionaron 55 pacientes con manifestaciones clínicas o sub-clínicas de infección cervical por VPH, solas o asociadas a otras lesiones por VPH del tracto genital inferior, estudiando igualmente a las parejas correspondientes. Se obtuvo para estudio histológico, muestras por biopsia dirigida por colposcopia de las lesiones cervicales, las cuales se procesaron con la técnica de rutina Hemotoxilina-Eosina, se observaron con microscopio de luz y se selecionaron cortes para la aplicación de peroxidasa antiperoxidasa. Se estudio la relación de los resultados con la edad, gestaciones, paridad, sexarquia, citología, localización de las lesiones genitales, infección de la pareja, colposcopia e histopatología


Assuntos
Adulto , Humanos , Feminino , Colo do Útero/patologia , Imunoquímica , Papiloma/classificação , Peroxidases/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico
17.
Biol Chem Hoppe Seyler ; 368(8): 991-9, 1987 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3663331

RESUMO

The antigen-specific immune suppression by gelonin-antigen conjugates was tested in two different systems: (i) the horseradish-peroxidase-stimulated T-cell proliferation in vitro and (ii) in vivo with experimental autoimmune myasthenia gravis (EAMG) in the rat. For this, the phytotoxin gelonin, a glycoprotein from Gelonium multiflorum, was purified and linked to the respective antigens. For the in-vitro assay a lymph node cell suspension from rats immunized with horseradish peroxidase was cultured in the presence of this protein and proliferation was measured by [3H]thymidine uptake. In-vitro proliferation was significantly inhibited by adding gelonin-horseradish peroxidase conjugates. The therapeutic effects of antigen-gelonin conjugates were tested in the rat model EAMG. For these experiments rats were immunized with purified nicotinic acetylcholine receptor from electric fish in order to develop EAMG. The success of the immunization was monitored by the change in physical performance tests, the change in anti-acetylcholine receptor antibody titer, and by the change in the number of ionic endplate channels using a novel electrophysiological method. The latter method permits a very accurate assay of functional damage of acetylcholine receptor at the endplate and correlates well with the clinical severity of the disease. Rats were conventionally immunized with acetylcholine receptor from electric fish. After the onset of EAMG as measured by physical performance tests and rise in antibody titer a group of the animals was injected with an acetylcholine receptor-gelonin conjugate and this treatment was repeated seven days later. The loss in functional acetylcholine receptor was significantly smaller in the therapy group than in the untreated EAMG group.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Antígenos/administração & dosagem , Miastenia Gravis/tratamento farmacológico , Proteínas de Plantas/uso terapêutico , Animais , Meios de Cultura , Eletrofisiologia , Feminino , Imunização , Linfonodos/citologia , Peroxidases/imunologia , Peroxidases/uso terapêutico , Ratos , Ratos Endogâmicos , Receptores Colinérgicos/metabolismo , Proteínas Inativadoras de Ribossomos Tipo 1 , Espectrometria de Fluorescência
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